Various burners have been used in industrial furnaces to melt glass forming ingredients or metals, to incinerate waste or to combust chemical reactants. Generally, these burners comprise a passageway for ejecting fuel and a passageway for emitting oxidant, as shown by, for example; U.S. Pat. No. 5,104,310 and Brazilian Patent No. 8,503,088. The fuel is normally atomized with pressurized air, pressurized steam or mechanical fuel atomizing means and combusted with a substantial amount of oxidant. When the oxidant employed is either an oxygen enriched air or technically pure oxygen rather than air, the combustion efficiency may be enhanced. Much less energy, for example, may be needed for handling oxygen enriched air or pure oxygen since oxygen enriched air or pure oxygen contains less inert nitrogen than does air for an equivalent amount of oxygen. However, the pure oxygen or oxygen enriched air is known to increase the combustion temperature. Thus, failure to control the combustion temperature and flame length resulting from using the pure oxygen or oxygen enriched air can damage the burners and/or their associated furnaces. Moreover, an unsafe condition may be created if fuel, such as oil, is allowed to flow into a passageway which is used for emitting oxidant. The oil in the oxygen pipe, for example, can lead to an explosion since it can be ignited in the presence of oxygen. Therefore, there is a genuine need for apparatus and processes, which are useful for mitigating or alleviating such problems.